The boy was only discovered at around midday in a weakened state, at the end of the school day, and reportedly died on the way to the International Hospital of Bahrain, it said.

Police confirmed the tragedy, which has caused shockwaves across the country, with many people taking to social media websites to express their sorrow and anger.

The Interior Ministry said an investigation had been launched and sources told the newspaper the Bahraini bus driver and the bus supervisor were being questioned.

"The Education Ministry has suspended all studies at the Al Rawbi Private School for all ages, from kindergarten up to secondary school," said an Education Ministry statement.

"School officials have been referred to the Interior Ministry and the Public Prosecution to inform them of the incident.

"The authorities summoned the school's owner and the kindergarten principal as well as a number of officials for interrogation in light of the incident and for not reporting it to the ministry." - TradeArabia News Service